I have had two CS's and believe it or not, I have never used the factory preset. Since I have got the second CS, I have experimented a great deal with the settings. I found the the 525 setting works great in trashy spots. I have tried higher sens, no notches, and many different threshold settings. The last two times out I have happened on a combination that gets incredible depth in my soil. This setting is 99 dis, 7 sens, -5 threshold, tabs and foil notched. Volume is a personal preferance. I found three coins at an honest 9 inches and these came from a pretty trashy spot. It seems that this setup is pretty close to the factory preset. I have found these deep coins would get high whisper and they would remain when I checked from another angle, but the tone might be different. I hope that doesn't sound confusing. I have read that the CS could be swept faster than a CZ, but I seem to get the best depth with a slower sweep. I also ground balance like some of the pros do, that is I GB in all metal and I don't lift the coil as high as the manual states. I believe that this method must GB slightly positive, but I don't know that for sure. I do think the depth is greater with this method of ground balancing. These are only my thoughts and what works in my neck of the woods. R.L.